I want to buy a ukulele, (uke) because I want to learn to play it, I’m really into music. What are the requirements for a good uke?

Also, if I go to Mexico, how much would it cost?

(Would this be good: http://cgi.ebay.com/NEW-UKULELE-UKELELE-UKE-4-STRING-SOPRANO-STANDARD-SIZE_W0QQitemZ190319869326QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item2c4ff2bd8e&_trksid=p3286.c0.m14&_trkparms=65%3A12|66%3A2|39%3A1|72%3A1205|293%3A1|294%3A50#ebayphotohosting)
Dude, Hawaii is like on the other side of the world for me. LOL!